Electronic device with gaze tracking system

Abstract

An electronic device may have a display and a gaze tracking system. Control circuitry in the electronic device can produce a saliency map in which items of visual interest are identified among content that has been displayed on a display in the electronic device. The saliency map may identify items such as selectable buttons, text, and other items of visual interest. User input such as mouse clicks, voice commands, and other commands may be used by the control circuitry in identifying when a user is gazing on particular items within the displayed content. Information on a user's actual on-screen point of gaze that is inferred using the saliency map information and user input can be compared to measured eye position information from the gaze tracking system to calibrate the gaze tracking system during normal operation of the electronic device.

What is claimed is: 
     
       1. An electronic device, comprising:
 a display; 
 control circuitry that is configured to display content on the display during normal device operation and that is configured to produce a saliency map identifying a location of an object of visual interest in the displayed content, wherein the saliency map is a probability density map in which features of visual interest are highlighted; and 
 a gaze tracking system, wherein the control circuitry is configured to calibrate the gaze tracking system during normal device operation by comparing a measured on-screen point of gaze from the gaze tracking system to the location of the object of interest identified by the saliency map. 
 
     
     
       2. The electronic device defined in  claim 1  wherein the gaze tracking system includes at least one light source and at least one camera. 
     
     
       3. The electronic device defined in  claim 2  wherein the control circuitry is configured to display repositionable windows on the display and wherein the object of interest is a selectable button associated with a displayed repositionable window. 
     
     
       4. The electronic device defined in  claim 2  wherein the object of interest comprises text. 
     
     
       5. An electronic device, comprising:
 a display on which a selectable object is displayed; 
 a gaze tracking system that is configured to measure eye position information; 
 an input device that is configured to receive a command to select the selectable object; and 
 control circuitry that is configured to:
 determine a first on-screen location based on the measured eye position information; 
 determine a second on-screen location at which the selectable object is displayed; and 
 in response to the input device receiving the command to select the selectable object and the first on-screen location being within a threshold distance of the second on-screen location, calibrate the gaze tracking system based on the measured eye position information and the second on-screen location. 
 
 
     
     
       6. The electronic device defined in  claim 5  wherein the gaze tracking system comprises:
 a light source configured to emit light; and 
 a camera configured to capture images containing reflections of the light. 
 
     
     
       7. The electronic device defined in  claim 6  wherein the control circuitry is configured to produce the eye position information from the images. 
     
     
       8. The electronic device defined in  claim 5  wherein the display comprises a head-mounted display. 
     
     
       9. The electronic device defined in  claim 5  wherein the control circuitry is configured to produce a saliency map that identifies objects of visual interest in the content on the display and wherein the control circuitry is configured to identify the second on-screen location from one of the objects of visual interest identified in the saliency map.